1. Field of the Invention
The present invention relates to an electric power tool, and specifically to an electric power tool having an illuminator that illuminates a work spot.
2. Description of the Related Art
U.S. Pat. No. 6,318,874 B1 discloses an electric power tool that comprises a motor for driving a tool, a power source unit (battery) that applies DC voltage to the motor terminals of the motor, a main switching circuit that makes/breaks an electrical connection between the motor terminals and the power source unit, and a forward-reverse switching circuit that switches a direction of the DC voltage which is applied from the power source unit to the motor terminals via the main switching circuit.
In this electric power tool, when the main switching circuit is turned ON, DC voltage is applied to the motor terminals and the DC motor starts driving the tool. When the main switching circuit is turned OFF, the DC voltage application to the motor terminals is suspended and the drive of the DC motor is stopped.
Direction of the DC voltage which is applied to the motor terminals can be switched by the forward-reverse switching circuit, so that the direction to which the tool is driven by the motor is freely switched between the forward and reverse direction.
The electric tool described above further comprises an illuminator that illuminates a work spot where the tool is used, and a switching device for turning ON/OFF the illuminator. The switching device has a base terminal. When a base voltage applied to the base terminal is higher than a threshold level, the switching device electrically connects the illuminator to the power source unit. In other words, light of the illuminator is turned ON. To the base terminal of the switching device, a motor side contact of the main switching circuit is electrically connected. Accordingly, when the main switching circuit is turned ON, a voltage at or higher than a threshold level is applied to the base terminal from the power source unit and the illuminator is turned ON. At the same time, the motor starts driving the tool. When the main switching circuit is turned OFF, the DC voltage application at or higher than a threshold level to the base terminal from the power source unit is suspended, and the illuminator is turned OFF. At the same time, the drive of the tool by the motor is stopped. In this electric power tool, illuminator is turned ON and OFF in conjunction with the starting and stopping of driving the tool by the motor.